Question

The hammer of a pile driver weighs 3800 N and must be lifted
3.20 m vertically at constant speed in2.00 s. What horsepower must
theengine provide to the hammer? hp

Okay this is what I did I realized that weight was not yet
amass so I used the Equation F=ma and I figured thatacceleration
3800=m(9.8) then I took3800/9.8=m

and then m=387.7 once I found my m I used the Equationmgh mass
gravity hieght lifted so I used 387.7*9.8*3.2 this was myWork.
which ended as 12160 J then I took the time 2 seconds andwent
12160/2 which gave me 6080 Watts to get HP I diveded by746Watts
which gave me 8.14 HP AND it was Right!!!! Yes! I got itright
without help!!!